7 uses of DRUPAL_MINIMUM_PHP

hook_requirements in drupal-7.x/modules/system/system.api.php
Check installation requirements and do status reporting.
install_profile_info in drupal-7.x/includes/install.inc
Retrieves information about an installation profile from its .info file.
system_requirements in drupal-7.x/modules/system/system.install
Implements hook_requirements().
update_fix_d7_install_profile in drupal-7.x/includes/update.inc
Register the currently installed profile in the system table.
update_prepare_d7_bootstrap in drupal-7.x/includes/update.inc
Performs extra steps required to bootstrap when using a Drupal 6 database.
_system_rebuild_module_data in drupal-7.x/modules/system/system.module
Helper function to scan and collect module .info data.
_system_rebuild_theme_data in drupal-7.x/modules/system/system.module
Helper function to scan and collect theme .info data and their engines.